Link errorwhile compiling decode video application

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#258 opened on May 15, 2019 0 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty: 3/5
Estimated time: 1-2 days
Newbie friendliness: 35/100

Issue type: Bug
Clarity: Needs clarification
Activity status: Stale
Tech stack: c
Domain: build-system

Research direction

Start with doc/example/decode_video.c and the examples target around Makefile:108, then inspect how the Windows example linker inputs are configured. Reproduce make examples and trace the link command; done means the modified decode_video example links successfully without the pthread_create unresolved-symbol errors.

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Description

Hi,

I have modified the doc/example/decode_video.c to start a thread using the pthread_create() call. While compiling the FFMPEG Example with this new (replaced) decode_video.c I get the link error as below:

**> $ make examples

LD doc/examples/decode_video_g.exe
decode_video.o : error LNK2019: unresolved external symbol pthread_create referenced in function main
doc/examples/decode_video_g.exe : fatal error LNK1120: 1 unresolved externals
make: *** [Makefile:108: doc/examples/decode_video_g.exe] Error 96**

I have libpthreadGC1.a and libpthreadGC2.a from Windows pthread pkg but need to understand how to include this pthread lib here to avoid this link error. Do I need to make changes to any Makefile in FFmpeg or include in config parameter?

Thanks

Dominant language: C++
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